texture = "http://www.roblox.com/asset/?id=686544830" -- put id there, then set last digit one number back

local A = game.Workspace:GetChildren()
local B = game.Workspace:GetChildren()
local C = game.Workspace:GetChildren()
local D = game.Workspace:GetChildren()
local E = game.Workspace:GetChildren()
local F = game.Workspace:GetChildren()
for i,v in pairs(A) do
if v:IsA("Part") then
local d =       Instance.new("Decal",v)
v.Decal.Face = "Top"
v.Decal.Texture = texture
v.Anchored = true
end
end

for i,v in pairs(B) do
if v:IsA("Part") then
local s = Instance.new("Decal",v)
s.Face = "Front"
s.Texture = texture
end
end

for i,v in pairs© do
if v:IsA("Part") then
local h = Instance.new("Decal",v)
h.Face = "Back"
h.Texture = texture
end
end

for i,v in pairs(D) do
if v:IsA("Part") then
local j = Instance.new("Decal",v)
j.Face = "Left"
j.Texture = texture
end
end

for i,v in pairs(E) do
if v:IsA("Part") then
local k = Instance.new("Decal",v)
k.Face = "Right"
k.Texture = texture
end
end

for i,v in pairs(F) do
if v:IsA("Part") then
local l = Instance.new("Decal",v)
l.Face = "Bottom"
l.Texture = texture
end
end
Try this